var lastname;
function checkValue(input,formloan) {
  if (input.name == 'purchaseprice' || input.name == 'monthlypayment'){
	   lastname = input.name;
	}
	if(input.value == '') {
	    input.value=input.defaultValue;
	}
  if(input.value > 9999999 || input.value < 0) {
	    alert('Value out of bounds');
	    input.value=input.defaultValue;
	}
  var str = input.value;
  if (isNaN(str)) {
	    var straray = str.split(',');
	    if (straray[1]) { 
		str = straray[0].concat(straray[1]);	
	    }	
	    if (straray[2]) { 
		str = str.concat(straray[2]);	
	    }	
	    if (str.substr(0, 1) == "$") {
		str = str.substr(1, str.length);
	    }
	    if (str.substr((str.length - 1), str.length) == "%") {
		str = str.substr(0, (str.length - 1));
	    }

	    input.value = str;
	    if(isNaN(input.value)) {
		alert('This field requires numeric data');
		input.value=input.defaultValue;   
			}
  }
  add_input(formloan);
}

function add_input(formloan) {
  if (lastname == 'monthlypayment') {
      check_payment(formloan);
      }
      else {
        var total_cost;
        total_cost = (formloan.purchaseprice.value * 1 - formloan.downpayment.value);
				var i = formloan.apr.value;
				i = i / 100.0;
				i /= 12;
        var pow = 1;
        for (var j = 0; j < formloan.loanterm.options[formloan.loanterm.selectedIndex].value; j++) {
            pow = pow * (1 + i);
						}
				formloan.monthlypayment.value = Math.round((total_cost * pow * i) / (pow - 1));
				if(isNaN(formloan.monthlypayment.value)) {
						alert('This field requires a non-zero value'); 
					}
				return false;
      }	
}

function check_payment(formloan) {
  var purchase;
	purchase = formloan.monthlypayment.value;
	
  var i = formloan.apr.value;
	i = i / 100.0;
	i /= 12;
	var pow = 1;
  for (var j = 0; j < formloan.loanterm.options[formloan.loanterm.selectedIndex].value; j++) {
      pow = pow * (1 + i);
			}
	var total_cost = (formloan.monthlypayment.value * (pow - 1)) / (pow * i);
	total_cost = ((total_cost * 1) + (formloan.downpayment.value * 1));
	formloan.purchaseprice.value = Math.round(total_cost);
	formloan.monthlypayment.value = purchase;

    formloan.purchaseprice.value=outputMoney(Math.round(formloan.purchaseprice.value));

	return false;
}

function selectValue(field) {
         field.select();
}